1. Field
The following description relates to an apparatus for obtaining status information about a crystalline lens of a person's eyeball, and optical/electronic equipment including the apparatus.
2. Description of the Related Art
A person has an eyeball structure that may adjust a thickness of a crystalline lens to focus objects with different distances from the crystalline lens. A person's eyeball focuses on objects by increasing the thickness of the crystalline lens while the person views objects located close to the crystalline lens and by decreasing the thickness of the crystalline lens while viewing objects far from the crystalline lens. Accordingly, the radius of curvature of the crystalline lens (specifically, the cornea surrounding the crystalline lens) also decreases or increases depending on a distance from the crystalline lens to an object.
Optical devices, such as a telescope, a microscope, a camera, and the like, or direct view displays such as a head-mount display, generally include an external focusing terminal or a mechanical focusing device that may correct focus deviations based on a person's sights and/or various environments. A person who utilizes such an optical device or direct view display may manually manipulate the external focusing terminal to correct focus deviations or conduct refocusing.
Various methods for detecting changes in thickness of a crystalline lens to obtain status information of the crystalline lens have been proposed. For example, Japanese Laid-open Patent Application No. 2000-139841, entitled “a Method of Measuring Changes in Thickness of Crystalline Lens, and a Training System for Self-Care of Pseudomyopia Using the Method” relates to a method of irradiating an infrared light on an eyeball, photographing the eyeball with a CCD camera, and analyzing the photographed images using a computer to measure changes in thickness of a crystalline lens. Also, Japanese Laid-open Patent Application No. 2006-195084 entitled “display apparatus” relates to a display apparatus for estimating the thickness of a crystalline lens using light reflected from an eyeball and displaying images adaptively according to the status of the eyeball. According to the conventional techniques, a light emitted from a light source is incident to an eyeball via a translucent mirror and a pair of convex lenses, and a is reflection light that is to be measured by a crystalline lens thickness measurer passes through the convex lenses and is deflected by the translucent minor, so that the path of the reflection light is directed towards the crystalline lens thickness measurer.
Meanwhile, there are currently many displays that support Full High Definition. Thus, in spite of development of data compression technologies, an amount of video data that has to be processed is increasing as a result of the high resolution. The increase in the amount of video data that has to be processed increases the load of an encoder (or an image acquisition apparatus having an encoder). In this example, an image acquisition apparatus for acquiring stereoscopic images or a display for reproducing the stereoscopic images has greater load because the apparatus has to process left-eye and right-eye images.